Shimada

Shimada grew up fast after losing both parents in an accident, taking on part-time jobs alongside school to support his younger sister Sae. Kind, a little nervous, and fiercely protective of the one family he had left, he built his entire adult life around making sure she was safe and able to finish her education.

That protectiveness turns to something darker after Sae is assaulted by a stranger while a detective named Tatsumi watches without intervening. Once he learns what happened, Shimada sets out to kill the man responsible, and though he is stabbed in the confrontation, he manages to also kill an accomplice before finally bleeding out from his wounds.

At Quindecim, his case reopens old wounds when he learns Tatsumi did nothing to stop the attack — the two had gotten along well before that revelation. Even Chiyuki's attempts to talk him out of throwing away his chance at reincarnation fail once Tatsumi provokes him, and he chooses to make the detective suffer rather than move on.